Engine starter



y 1931. J. w. FITZGERALD 1,804,757

ENGINE STARTER Filed Ma 19. 1928 2 Sheets-Sheet 1 i g L I 5 I N IT,

@WJW M72727 Vkfizzg mial y 1931- J. w. FITZGERALD 1,804,757

ENGINE STARTER Filed May 19. 1928 2 Sheets-Sheet 2 i I mm JOHN VT. FITZGERALD, MILW'AUKEE, WISCONSIN, ASSIGIIOR T0 BRIGGS AND STRAT- Patented May 12, 1%31 tear- 57 TON" CORPOR ATION, OI" MILWAUKEE, "WISCONSIN, A GQEEGBATION 0F DELA'WARE ENGINE STARTER Application filed May 19,

lhis invention relates to startersfor automobile engines, marine engines, airplane engines and the like and has as an object the pro vision of an improved starter of simplified construction to reduce production costs and, at the same time, provide a more eiiicient and practical structure,

The starters now in common use are substantially as illustrated in the British patent toGalloway, et al., No. 6,824 of 1884, wherein a pinion gear is adapted to be thrown into mesh with a ring gear preferably fixed to the engine fly wheel when the starting motor is operated and adapted to be disengaged therefrom upon the speed of the engine fly wheel becoming greater than that of the starter motor. This structure is not complete and hence.

not practical in that should the teeth of the gears fail to be in register whenthey engage, breakage results and in Letters Patent No. 1,116,370, issued Vincent Bendix, November 10, 1914, a yieldable drive connection for the starter gear shaft permits the necessary give should the teeth of the gears fail to mesh.

The latter structure is open to mechanical objections, as, the spring crystallizes from constant use and when broken the entire start-er is inoperative and this invention-has as another object the provision of a starter for engines wherein the starter shaft is in substantially one pieceand has means for permitting the desired give in the event the gears fail to properly mesh instantly upon the starter gear engaging the engine gear.

A more specific object of this invention resides in the provision of an improved starter for engines wherein the'drive unit is yieldable axially under stress in the event the teeth of the starter gear fail to align with the teeth of the engine gear instantly upon their engagement.

lVith the above and other objects in view which will appear as the description proceeds, my invention resides in the novel construction, combination and arrangement of parts substantially as hereinafter described and more particularly defined by the appended claims, it being understood that such changes in the precise embodiment of the 1928. Serial no. 279,174.

herein'disclosed invention may be made as come within the scope of the claims.

In the accompanying drawings, I have illustratedseveral complete examples of the I physical embodiment of my invention-constructed according to the best modes I have so far devised for the-practical application of the principles thereof, and in which:

Figure 1 is a view, partly in side elevation and partly in section, of an electric starting motor embodying one form of my invention;

Figure 2 is a view similar to Figure 1 illustrating a slightly modified form of my invention; and

Figure 3 is a fragmentary view, partly in section and partly in elevation, illustrating still another modified form of my invention.

Referring now more particularly to the accompanying drawings, in which like numerals designate like parts throughoutfthe several Views, 5 designates an electric motor of suitable design and construction including a rotor 6 having its shaft 7 j ournaled in bearings 8 at opposite ends of the motor hous ing 9. One end of shaft projects beyond the housing and is provided withan enlargement 10 which is fast thereto and may be integral therewith if desired and is provided with external'helical threads 11 on which a pinion 12 is threaded. I

In that form of my invention illustrated in Figures 1 and 2, which is the out-board type of starter, the shaft 7, is preferably provided with a bearing support 13 positioned at theside of the engine ring gear 14 opposite to the starter motor, as best shown in Figures 1 and 2. The ring gear 14 is preferably can ried bythe fly wheel 15 of the engine, not shown, and as the rotor 6 is rotated by the closing of the motor circuit, not shown, the helical threads 11 cause the pinion 12'to be advanced axially and. engage thegea'r l l of the motor, its engagement with the gear 14 being limited by a shoulder or collar 16 and its movement inwardly being restricted by a shoulder or a stop 17.

In-the event the teeth of the pinion and" arrested until the teeth register. It is in this particular that the structure illustrated in the British patent to Galloway fails and I provide normally inactive means for permitting'this axial yielding movement by either permitting end thrust on the part of the drive shaft or on the part of the entire motor unit.

In Figure 1, the shaft 7 of the starter motor has a considerable endwise or axial movement which is limited in one direction by a stop collar 18 abutting the adjacent bearing 8, and which is yieldably resisted in the other direction by an expansile spring 19 enclosed within an end cap 20 fixed to the motor housing 9 and compressed between the cover 21 of the housing 20 and. a washer 22 carrying a ball 23 engaging with a recess in the adjacent end of the shaft 7. As the pinion gear engages the gear 14, should the teeth of the gears fail to register, the entire drive unit including the shaft 7, enlargement 10 and pinion gear is permitted axial movement against the spring 19 until the teeth of the gears 12 and 141 align, when the spring moves the unit to the right with reference to Figure 1, and the gear 12 continues its advance to its full starting position.

Vhen the engine, not shown, starts and the fly wheel rotates at a speed greater than that of the driving force of the motor 5, the pinion gear 12 is spun back to itsposition illustrated in Figure 1, as will be readily ap parent to those skilled in the art to which a structure of this character appertains.

In Figure 2, a modified form of my inven tion is illustrated in which the entire starting motor unit is movable axially under stress to permit the registering of the teethof the gears in the event they are out of line when the gears abut each other. This structure con sists of a mounting bracket 24 for the motor which is of approximately angular construction having elongated openings or slots 25 in its base through which the mounting bolts 26 of the motor 5 pass.

The motor is slidable on the mounting base for the length of the slots 25 but is yieldably urged to one limit by an expansile spring 27 compressed between the end housing or cover 28 of the motor and the upright portion 29 of the mounting bracket, an enlargement 3() carried by the upright 29 being engaged in the adjacent end of the spring to retain. it in position and the other end of the spring being engaged in a pocket 31 in the motor end member 28; The operation of this form of my invention is identical with that illustrated n1- Figure 1 with the exception that the entire motor unit is movable axially under stress.

In Figure 3 a slight modification of that form of my invention illustrated in Figure 1 is shown as applied to starters of the in-board type wherein the motor 5 has its housing of uniform cylindrical shape throughout and is slidably mounted in an outer casing or sleeve 32 in which it is held against rotary movement by elongated keys or guides 33, the motor being yieldably urged in one direction by an expansile spring 34 confined between the end wall 35 of the housing 32 and the end 36 of the motor.

From the foregoing description, taken in connection with the accompanying drawings, it will be readily apparent to those skilled in the art to which an invention of the character described appertains, that I provide an improved and novel starter for engines of all types which is of the simplest possible form to reduce production costs and which is of a highly eflicient and practical structure.

What I claim as my invention is:

1. An engine starter, comprising the combination with 'a member operatively connected with an engine, of a motor including .a housing, a rotor and a shaft having axial movement in the housing and projecting therebeyond, a drivin member mounted to travellongitudinally of the projected end of the shaft and into engagement with the engine member and to rotate therewith, spring means engaged with the housing adjacent the I opposite end of the shaft, and anti-friction means disposed between the free end of the spring means and said opposite end of the shaft, whereby the spring means yieldably resists axial movement of the motor shaft in a direction opposite to the direction of move ment of the driving member to engage the engine member.

2. An engine starter, comprising the combination with a member operatively connected with an engine of a motor including a housing, a rotor and a shaft having axial movement in the housing and having one end projecting therebeyond, a driving member mounted to travel longitudinally of the projected end of the shaft into engagement with the engine member and to rotate therewith, an expansive spring having one end engaged with the motor housing adjacent the opposite end of the motor shaft, a washer member closing the free end of the expansive spring, and a ball member confined between the washor member and the said opposite end of the shaft, whereby the spring yieldably resists axial movement of the motor shaft in a direction opposite to the direction of movement of the driving member to engage the engine member.

In testimony whereof I have hereunto affixed my signature.

JOHN W. FITZGERALD. 

